Animating pie chart with Google Visualization

I am experimenting with google charts. I want a pie chart to animate from 0% to 75% (see the image below). I am attempting to achieve this through google charts. I am creating two sets of data, one will start at 99%, the other at 1%. I want to invert and animate these. I have achieved changing the values through animation, but cannot figure out how to get them to animate.